KnowledgeWorks and Prolog User Guide > 5 The Programming Environment > 5.9 Monitor Windows


5.9.1 Forward Chaining History

Figure 5.12 KnowledgeWorks Forward Chaining History

The Forward Chaining History may be viewed by choosing KnowledgeWorks > FC History . This displays the rules which the forward chaining engine has fired. The left pane lists sequentially the contexts which have been executed, with the cycle number in which they were entered. These can be clicked on to show in the right pane, the history for that context. The rules in it are listed down the left, and the cycle numbers along the top, forming a two dimensional grid.

Each position in the grid indicates the status of the rule in that cycle. A colored box indicates that the rule fired. A half-colored box indicates that the rule fired, but that the invocation of the backward chainer on the right-hand side failed at some point. There can only be one colored or half-colored box per cycle. An outlined box indicates that the rule was in the conflict set but was not chosen to fire. Absence of any icon indicates that the rule was not even in the conflict set.

If the forward chaining history is displayed while a rule is executing (for example, while the rule is being single stepped) a half-colored box is displayed as execution is not complete.

The Rule menu can be used in the same way as in the Rule Browser, described in The Rule Browser. It applies to the selected rule in the FC Cycles pane.

The Show Inferencing State dropdown allows you to choose which named inferencing state is examined.

This tool is not available when debugging is turned off.


KnowledgeWorks and Prolog User Guide (Unix version) - 22 Dec 2009